Combine 1/2 c of the sugar, with the cornstarch, salt, ginger, nutmeg, and cinnamon. Add the pumpkin and milk. Mix well. Cook over medium heat in a large flat saucepan until thickened, stirring constantly. Add the gelatin mixture and the margarine, stirring until dissolved. Cook until partially set. Cool. Stir to prevent a hard crust from appearing.

Beat the egg whites until soft peaks form (about 20 minutes), and gradually beat in the remaining 1/2 c sugar. Continue until very stiff, and fold into the cooled pumpkin mixture. Pour into pastry shell. Garnish with crushed pecans.